The display of electronic digitized media on a computer display screen is very well known in the art, and is often accomplished by displaying the digitized media inside a window. However, the window dimensions are often smaller than the entire display of the media, with the result that the window frame cuts off large portions of the media. The media often cannot be properly sized within the window frame if it is particularly complex and sizing down will cause the text or graphics to be unreadable.
Because the electronic digitized media is likely to overlap the size of the window, several methods are proposed in the prior art for permitting the user to bring hidden portion of the media into view of the window.
For example, as shown on page 8 of "Microsoft".RTM. Windows.TM. Users Guide", Copyright 1992, Microsoft Corporation, a pair of scroll bars are provided at the peripheral edge of the display window when the electronic digitized media is actually larger in size than the physical display window. A vertical scroll bar (designated by vertically pointing "up and down" arrows) permits vertical movement of the media within the bounds of the window. Movement is activated by placing the graphical marker of a pointing device (e.g. a mouse cursor or a roller ball) over the scroll bar and pressing a button on the pointing device. If the graphiced marker is placed in either the up or down scroll arrow, the media is moved up or down one line, respectively. If the graphical marker is placed on the scroll bar, then the media is moved up or down one screen. If the scroll box is dragged in the scroll bar, the media is moved concurrently to a new vertical position until dragging ceases.
A horizontal scroll bar (designated by left and right pointing arrows) provides horizontal movement of the media with the bounds of the window. Again, movement is activated by the user placing the graphical marker over the horizontal scroll bar and pressing a button on the pointing device. If the graphical marker is placed on either the left or the right scroll arrow, the media is moved up or down one column. If the graphical marker is placed on the scroll bar, then the media is moved left or right one full screen. If the scroll box is dragged in the scroll bar, the media is concurrently moved to a new horizontal position until dragging ceases.
There are a number of problems associated with the use of horizontal and vertical scroll bars. Very course movements of the pointing device usually traversing the window, are required to locate the graphical marker over a bar area for selection, and movement in placement of the graphic marker is prone to error, particularly for less experienced or occasional computer users. For example, sensitivity and tracking speed varies between systems, and as a result, overshoot and undershoot placement problems are common amongst users. Other placement problems depend upon the experience of a user with a particular pointing device used in the system.
Also, the scroll bars added to the window frame reduce the client or display area for text within the window. In addition to the foregoing, simple diagonal movement of the media within the window is not possible, but instead, many successive operation on the horizontal and vertical scroll bars are desirable to achieve a diagonal movement effect.
The Asymetrix.RTM. Multimedia Toolbook.RTM., Copyright 1989, 1991 by Asymentrix Corporation, provides a software construction set for windows. A number of multimedia wigets, such as horizontal and vertical sliders, buttons, and link sliders, are provided to permit movement of media within a window.
The sliders and buttons are prone to the same problems of the previously described scroll bars provided by Microsoft Windows, namely the lack of sensitivity of the pointing device in the users hands, and the lack of an ability of simple diagonal movement. The sliders and buttons also encroach into the client area of the window in this system.
While the link sliders provide diagonal movement of the media, movement is restricted to that of the aspect ratio of the window, and as such, does not permit diagonal movement of the entire media within or into the viewing area.
Another approach for providing movement of media within a window involves a point-click-drag operation as described in U.S. Pat. No. 5,196,838 of Apple Computer Inc. Movement of the graphical marker into the window area turns the marker into an iconic "hand". By clicking a button on the tracking device, the media is effectively attached to the marker and movement of the pointing device permits the movement of the media in the same direction. While this approach does overcome problems associated with the horizontal and vertical to sliders discussed above, a plurality of point-click-drag-release operation are required to adjust the view and to navigate the entire media, and this plurality of operations if often frustrating to the users and renders navigation difficult.
The foregoing problems of the prior art are further amplified in Notepads and Thinkpads.TM. which employ a Trackpoint II pointing device. The Trackpoint II device requires an even greater manual dexterity than the ordinary mouse tracking device, and positioning a graphical marker accurately is even more difficult.
In addition to the foregoing, none of the prior art attempts provide a "gradient of speed" for moving the media in or into a window frame.